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Related papers: Gravity and Quantum Fields in Discrete Space-Times

200 papers

Motivated by quantum-mechanical considerations we earlier suggested an alternative action for discretised quantum gravity which measures the perimeter of the space-time and has a dimension of length. It is the so called perimeter action,…

High Energy Physics - Theory · Physics 2018-02-28 George Savvidy

We briefly overview the development of Euclidean quantum gravity in four dimensions regarded as a branch of statistical mechanics of discretized random manifolds.

High Energy Physics - Lattice · Physics 2008-02-03 A. Krzywicki

We propose a new class of quintessence models in which late times oscillations of a scalar field give rise to an effective equation of state which can be negative and hence drive the observed acceleration of the universe. Our ansatz…

Astrophysics · Physics 2009-10-31 Varun Sahni , Limin Wang

We employ scattering amplitudes in curved space to model the dynamics of a light probe particle with mass $m$ orbiting in the background spacetime induced by a heavy gravitational source with mass $M$. Observables are organized as an…

High Energy Physics - Theory · Physics 2024-04-02 Dimitrios Kosmopoulos , Mikhail P. Solon

We study the quantum geometry of the fuzzy sphere defined as the angular momentum algebra $[x_i,x_j]=2\imath\lambda_p \epsilon_{ijk}x_k$ modulo setting $\sum_i x_i^2$ to a constant, using a recently introduced 3D rotationally invariant…

Quantum Algebra · Mathematics 2020-04-30 Evelyn Lira Torres , Shahn Majid

We consider a model of Dirac fermions coupled to flexural phonons to describe a graphene sheet fluctuating in dimension $2+d$. We derive the self-consistent screening equations for the quantum problem, exact in the limit of large $d$. We…

Mesoscale and Nanoscale Physics · Physics 2014-04-02 Francisco Guinea , Pierre Le Doussal , Kay Joerg Wiese

We extend Dirac's approach about the quantization of the electric charge to the case of gravitational configurations. The spacetime curvature is used to define a phase-like object which allows us to extract information about the behavior of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Leonardo Patiño , Hernando Quevedo

A two dimensional matter coupled model of quantum gravity is studied in the Dirac approach to constrained dynamics in the presence of a cosmological constant. It is shown that after partial fixing to the conformal gauge the requirement of a…

High Energy Physics - Theory · Physics 2011-08-29 Jan Govaerts , Simone Zonetti

In recent years Quantum Superstrings and Quantum Gravity approaches have come to rely on non differenciable spacetime manifolds. These throw up a noncommutative spacetime geometry and we consider the origin of mass and a related…

General Physics · Physics 2007-05-23 B. G. Sidharth

The lattice gauge theory for curved spacetime is formulated. A discretized action is derived for both gluon and quark fields which reduces to the generally covariant form in the continuum limit. Using the Wilson action, it is shown…

High Energy Physics - Lattice · Physics 2015-01-29 Kristian Hauser Villegas , Jose Perico Esguerra

We show that the dimension of spacetime becomes complex-valued when its short-scale geometry is invariant under a discrete scaling symmetry. This characteristic can generically arise in quantum gravities, for instance, in those based on…

General Relativity and Quantum Cosmology · Physics 2017-08-15 Gianluca Calcagni

Linear perturbation is used to investigate the effect of gravitational softening on the retrieved two-armed spiral eigenmodes of razor-thin stellar discs. We explore four softening kernels with different degrees of gravity bias, and…

Astrophysics of Galaxies · Physics 2019-02-27 Sven De Rijcke , Jean-Baptiste Fouvry , Walter Dehnen

In this paper, we consider fermionic systems in discrete spacetime evolving with a strict notion of causality, meaning they evolve unitarily and with a bounded propagation speed. First, we show that the evolution of these systems has a…

Quantum Physics · Physics 2014-01-08 Terence C. Farrelly , Anthony J. Short

Recently we put forward a framework where the dark matter (DM) component within virialized halos is subject to a non-local interaction originated by fractional gravity (FG) effects. In previous works we demonstrated that such a framework…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-08 F. Benetti , A. Lapi , G. Gandolfi , M. Adil Butt , Y. Boumechta , B. S. Haridasu , C. Baccigalupi

We propose a unified model for dark matter haloes and central galactic objects as a self-gravitating system of semidegenerated fermions in thermal equilibrium. We consider spherical symmetry and then we solve the equations of gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-29 Bernardo M. O. Fraga , Carlos R. Arguelles , Remo Ruffini

Within the disk model framework used to approximately describe flattened galaxies, we develop an iterative method of determining column mass density from rotation curve supplemented with isotropic velocity dispersion profile. This…

Astrophysics of Galaxies · Physics 2015-12-08 Szymon Sikora , Łukasz Bratek , Joanna Jałocha , Marek Kutschera

We informally review the construction of spacetime geometries with multifractal and, more generally, multiscale properties. Based on fractional calculus, these continuous spacetimes have their dimension changing with the scale; they display…

High Energy Physics - Theory · Physics 2012-10-10 Gianluca Calcagni

This article begins by putting forth a model that shows how the storage and retrieval of information on a wave function that involves quantum entanglement behaves similarly to the concepts of length contraction and time dilation,…

General Physics · Physics 2023-09-01 Christopher I. Timms

Four-fermion interaction models are considered to be prototype models for dynamical symmetry breaking.The present review deals with recent developments in the studies of dynamical symmetry breaking in the four-fermion interaction models and…

High Energy Physics - Theory · Physics 2008-11-26 T. Inagaki , T. Muta , S. D. Odintsov

First, the present work is concerned with generalising constructions and results in quantum field theory on curved spacetimes from the well-known case of the Klein-Gordon field to Dirac fields. To this end, the enlarged algebra of…

General Relativity and Quantum Cosmology · Physics 2010-10-22 Thomas-Paul Hack